An optical device and a sensor system incorporating same are disclosed. The optical device includes a microresonator that has a core with input and output ports. The output port is different than the input port. The optical device further includes first and second optical waveguides. Each optical waveguide has a core with input and output faces. The output face of the core of the first optical waveguide physically contacts the input port of the core of the microresonator. The input face of the core of the second optical waveguide physically contacts the output port of the core of the microresonator.